Prostate cancer patients sometimes need to make an important decision: Go with radical surgery or opt for a watch-and-wait approach. But what if the patient doesn’t understand basic medical terms?

A new Emory University study reveals a severe lack of understanding of the most basic medical terms, including incontinence and urinary function.

That raises concerns about whether patients are equipped to make meaningful decisions about their health care. The results of the study — involving 109 patients at urology clinics at Grady Memorial Hospital and Emory University Hospital in Atlanta — were just published in Cancer, a peer-reviewed journal of the American Cancer Society.

The participants agreed to answer questions about technical terms used in patient education materials that describe urinary, bowel and sexual function. The findings included the following: only 15 percent of the patients participating in the study understood the meaning of incontinence; less than a third understood urinary function and bowel habits; and less than half knew the meaning of the word impotence.

“I was surprised by the magnitude of it, by just how poorly understood these terms are — these terms we use every single day with every single patient,” said Dr. Viraj Master, a physician and researcher at Emory University’s Winship Cancer Institute and also a lead investigator of the study. “We have our work cut out for us.”

And while most of the patients in the study were being seen by a doctor for a prostate-related health concern, only a paltry 5 percent understood the function of the prostate.

The Emory study involved low-income patients with a median reading level of a ninth-grader, but other studies done on health literacy suggest this is a widespread phenomenon, Master said. Ultimately, Master said, a poor understanding of the meaning of potential side effects and other medical conditions could lead to a patient making decisions he may later regret.

Rich Lapin, vice president of the Georgia Prostate Cancer Coalition, an Atlanta-based nonprofit focused on raising awareness of prostate cancer and encouraging regular screenings to help detect prostate cancer in its earliest stages, said it’s critical for doctors to create an environment where patients feel comfortable asking questions.

Lapin, a 66-year-old prostate cancer survivor who was diagnosed with the disease more than a decade ago, said it’s also a good idea for patients to bring a loved one with them to doctor appointments to help take notes and ask follow-up questions.

Master said that Emory and Winship are working on computer programs to help explain medical terms and procedures.